This invention relates to liquid acid-containing solids for food products and more particularly, to dry, free-flowing powders containing substantial amounts of a liquid acid.
Liquid edible carboxylic food acids such as acetic acid, lactic acid, as well as phosphoric acid, acid phosphate salts and the like are commonly used as acidulating ingredients of edible liquid compositions to provide a desirable acid taste or tang. Historically, phosphates and phosphoric acid have been considered uniquely suited to application in foodstuffs, not only due to their favorable taste when compared with other strong mineral acids and their salts but also due to the fact that they are less expensive than other liquid organic acids. However, liquid phosphoric acid cannot be incorporated into dry powdered formulations as readily as can the solid organic acid. Dry solid acidulents containing phosphoric acid have not been successful because a large amount of a solid, dry carrier has been required in such mixtures in order that a dry free-flowing product containing a substantial amount of the acid might be provided. If a sufficient quantity of such an acidulent composition were to be added to the food product to provide the desired acidity, the resulting large amount of solid carrier would present problems in taste, appearance or feel of the food produced. On the other hand, increasing the amount of phosphoric acid relative to the amount of the carrier provides a desirable acid taste or tang but causes the mix of acid and carrier to be too wet and therefore to cake excessively.
Recent attempts to produce dry free-flowing powders from liquid acids which have been directed mainly to phosphoric acid and their solid acid salts are numerous. For example, U.S. Pat. No. 3,030,213 issued Apr. 17, 1962 discloses a dry acidulent for use in food and beverage formulations comprising a solid acid salt of phosphoric acid, phosphoric acid and sulphuric acid. The mixture comprises from 76 to 95% acid salt, from 3.5 to 22% phosphoric acid, and from 0.1 to 2% sulphuric acid. The above reference discloses in column three admixing the acids and salt at ambient temperatures followed by drying at around 100.degree. C.
Similarly, Miller in U. S. Pat. No. 2,715,059 issued Aug. 9, 1955 discloses a method of preparing a dry phosphoric acid-containing composition by admixing phosphoric acid with sodium acid pyrophosphate at ambient temperatures and heating the mixture in order to promote the "reaction".
Finally U. S. Pat. No. 3,657,010 issued Apr. 8, 1972 teaches acid-heat treatment of a hydrolyzed starch, specifically, heating a non-bulking hydrolized starch material having up to fifty percent monosaccharides with phosphoric acid to temperatures in the range of about 300.degree. F. to 370.degree. F. The molten mass is allowed to slowly cool and solidify and the resulting solid is ground into a powder.
It will be noted that the prior attempts to produce a stable free flowing acid powder directed primarily to a free flowing phosphoric acid containing powder has necessitated higher temperatures and in some cases added ingredients. Higher temperatures have traditionally been necessary in order to polymerize the carbohydrate material. This resulted in an anhydrous material which was relatively non-hygroscopic. In most instances these heat-treated dry acid compositions as well as those containing added ingredients are extremely susceptible to undergoing a browning reaction due at least in part to the acid having reacted with the carbohydrate material.